星载激光通信载荷高体分SiC/Al主镜及支撑结构设计

为了降低激光通信载荷在轨工作中空间环境对于光学系统的影响，提高通信质量以及跟踪精度，使用综合性能较好的高体分SiC/Al作为主镜材料，并通过有限元分析确定了主镜结构的几个重要优化参数。提出了一种一体式主镜柔性支撑，该结构避免了使用不同材料支撑组件线膨胀系数不匹配而产生的应力集中，提高了主镜面形的温度稳定性，并在此基础上降低了主镜及其支撑的总体质量，实现了光学系统的轻量化。仿真分析表明，该结构在重力释放条件下，主镜面形误差PV值为/52，RMS值为/275。工作环境发生4℃温度变化的情况下，主镜面形误差PV值为/11，RMS值为/71。主镜及其一体化支撑基频为208 Hz，主镜单独轻量化率为55.3%，进行一体化设计后主镜及支撑相比传统设计轻量化率为19.87%，能够满足总体指标要求。

Design of primary mirror and support structure of spaceborne laser communication terminal by the use of high-volume fraction SiC/Al

In order to reduce the effect of in-orbit space environment on the optical system of a laser communication terminal, improve communication quality and tracking accuracy, high-volume fraction SiC/Al that has better overall performance was used as the material of the primary mirror. Several important optimization parameters of the primary mirror structure were determined by the use of finite-element analysis. An integrated flexible support for primary mirror was proposed. The problem of stress concentration was solved because of using mismatch expansion coefficient materials for support assembly. The temperature stability of primary mirror surface shape was also improved. On the basis of this work, the weight of primary mirror and its support were reduced, a lightweight optical system was achieved. Simulation analysis shows that the PV of wavefront aberrations is /52 and the RMS of wavefront aberrations is /275, when the primary mirror under condition of gravity release. When the working environment temperature changes 4℃, the PV of wavefront aberrations is /11 and the RMS of wavefront aberrations is /71. The base frequency of primary mirror and its support is 208 Hz. The lightweight rate of primary mirror is 55.3%. After integrated design, the lightweight rate of primary mirror and its support is 19.87% compared to conventional design. In summary, system overall specifications requirements can be met.